Casting nets of life for the German wildcat

Dr. Friederike Scholz reports on how studies of the movements, habits and even genetics of wildcats are being used to establish migration corridors for these elusive felines.

These measures also benefit a large number of other endangered species

In addition to their direct loss, the dissection and isolation of habitats represents one of the most severe threats to biological diversity in central Europe and Germany.

Habitats with many rare animal and plant species are segregated by roads, railway tracks, residential areas, industrial sites, and extensive stretches of arable land. Remaining habitat patches are often isolated like scattered islands in the sea.

In particular, with more than 230,000 kilometres of roads, Germany has one of the World’s densest networks. For some endangered mammals like the wolf, otter and wildcat, road traffic is their most common cause of death in Germany today.

The problem of habitat fragmentation is exacerbated by the fact that, proceeding almost without restrictions, an average of more than 90 hectares of land is lost every day for new housing and street development; a reversal of this trend is not in sight.

The consequences of increasing habitat isolation are grave; inbreeding occurs in the isolated animal populations, which can lead to genetic depletion. Habitats of great ecological value are by themselves often too small to secure the survival of those species that need more space.

Additionally, a great number of landscape barriers hamper the natural re-colonisation of new habitats by many rare species. Their ability to adapt to changing living conditions is considerably constrained, particularly in times of climate change.

Thus the restoration of central Europe’s wildlife corridor network is one of the most significant challenges for nature conservation. In Germany, BUND (Friends of the Earth Germany) is dedicated to this task, through its involvement in two of Europe’s largest nature conservation projects.

The first, initiated by BUND, is the conservation of the “Green Belt” along the former inner German border strip, a project to ensure the long-term protection of a valuable habitat network of nearly 1,400 kilometres. The second, a Germany-wide project, is the 'Safety Net for the Wildcat'.

While in the past wildcats were endangered through extensive hunting, today’s main threats to the rare European wildcat are road traffic and habitat loss/fragmentation. In Germany there is still a population of between 5,000 and 7,000, most living in several isolated pockets in the country’s centre and south-west.

For their survival, wildcats in central Europe need structurally rich, near-natural deciduous/mixed forests. They prefer to give birth to their kittens in hollow trees, deadwood, brushwood heaps and dense bushes.

The wildcat is a forest dweller and it avoids open fields without cover such as large areas of cleared farmland. With the help of telemetric studies in central Germany, their habitat use was explored intensively and, based on the findings, a concept for a nationwide forest network was created - the “Wildcat Routing map”.

In the BUND project “Safety Net for the Wildcat”, this map serves as the scientific basis for the long-term creation of Germany’s 20,000 kilometre network of forest habitats. To achieve this, isolated forest areas are being reconnected through the planting of trees and bushes to create green corridors. Besides the wildcat, these measures also benefit a large number of other endangered species, such as the tree marten and lynx, as well as many forest-dwelling bird, bat and insect species.

In 2007 the first corridor was planted in Thuringia, connecting the Hainich National Park with the Thuringian Forest, which at the time was not populated with wildcats. There followed corridor plantations in Lower Saxony and Rhineland-Palatinate. Of equal importance are BUND’s campaigns to erect wildlife crossings, which enable animals to cross heavily trafficked roads, so reconnecting wildlife populations.

The basic prerequisite for the implementation of wildlife corridors is good collaboration between nature conservation organisations, public authorities, landowners, farmers and hunters. To achieve this, all interest groups should be actively involved in the discussions from the outset, to establish a steady dialogue. Additionally, cooperation with European partners has been initiated to raise international awareness and support for the issue of biotic connectivity.

The project “Safety Net for the Wildcat” will include a new sub-project, funded by the German Federal Agency for Nature Conservation. Its framework will comprise five new wildcat corridors, to be established over the next three years in Baden-Wuerttemberg, Hesse, Lower Saxony, Rhineland-Palatinate and Thuringia. The safety Net will be complemented by ecological improvements to forests around the Eifel National Park.

Another focus of the sub-project is to build a nationwide genetics database for the wildcat. For this purpose, wildcat hair recovered from lures placed in forests will be examined from 16 project regions. Valerian-treated wooden pegs serve as the lures, attracting wildcats particularly during the breeding season in winter, when they rub themselves against the pegs, frequently leaving behind some hair.

In addition to detecting the presence of wildcats, the hair can be examined genetically, allowing interpretation of the wildcat populations’ genetic structure. Based on these findings it’s possible to draw inferences about migratory movements of the animals, and the impact on them of landscape barriers. As biotic networking doesn’t stop at country borders, in the forthcoming stages BUND will focus on the close cooperation with its European neighbours.